Disintegration
by Ryne42
Summary: An AU of 4x07 in which Agravaine successfully kills Gaius. Dark!Merlin. Rated T for descriptions of violence.


**Category:** Gen (canon AU)  
**Characters/Pairings:** Merlin, Gaius, Alator, Gwaine, Arthur, Gwen  
**Rating/Warnings:** T (descriptions of violence)  
**Summary:** An AU of 4x07 in which Agravaine successfully kills Gaius. Dark!Merlin.  
**Notes:** This has been in the works for quite some time, and due to some unexpected muse, it's finally done. A few months ago I was doing a rewatch of series 4 with my sister and I realized that in my opinion, Merlin was at a tipping point during this episode, and if Gaius had died then he would've been pushed over the edge. And these are the consequences.

* * *

The last of Alator's pledge faded into silence and then there was only the sound of the torches sputtering in the cold air. Merlin could hardly breathe from happiness, and stood flummoxed and loose-limbed with relief and joy, huffing a sigh of amazement as the words sunk in. He was not alone. There were others who would fight with him, who believed in him, and Merlin allowed himself a moment, just a moment, to feel all he'd ever dreamed — happy and content and _recognized_ — before realizing that Alator still knelt before him. "Please," he said, the word catching on the lump in his throat, and he coughed to clear it away as he wiped the tears from his face. "Please stand. I'm not — you don't have to kneel to me." He coughed again as he felt Alator's eyes on him. "Please get up. I'm just — where's Gaius?"

"He is — alive," Alator said as he stood, gripping his staff tighter and looking away in shame. "Morgana wanted information and I was not gentle. But he is still alive." He looked askance at Merlin and added, "You'll be glad to know that he did not give up your secret easily."

"He could've died," Merlin said shortly. "What good would my secret be, in the face of that?"

Alator studied him for a moment, his expression unreadable, and then finally said, "You are not what I was expecting, Emrys." And before Merlin could ask for clarification, he turned away and said, "Come. I will take you to him."

- -o- -

They were not far into the tunnels before Merlin heard footsteps running toward them. "Gwaine — I _told him_ — why does nobody think that I can take care of myself?" Merlin muttered bitterly, and started forward. "Gwaine," he called into the darkness. "Gwaine, I told you to leave me behind if you found him, what're you—?"

The footsteps skidded to a halt and Merlin could barely see his friend in the torchlight. "Merlin," Gwaine croaked breathlessly, hopelessly, and Merlin's heart thudded; and as Gwaine stepped closer, his face looming into the torchlight, he looked bleak and lost, and Merlin knew. "Merlin, he's — I didn't—"

"No."

"He's gone, Merlin."

"_No_."

"It was Agravaine — he must have followed us, and — and he _killed him_, he—"

But a visceral sound tore out of Merlin and silenced Gwaine, and then he was running through the tunnels with Gwaine shouting after him, and he couldn't see a thing — couldn't see a damned thing in the dark — so Merlin conjured a light, and it didn't matter if Gwaine saw because Gaius was dead and _what good was his secret in the face of that?_

Torches flickered up ahead and Merlin put on a burst of speed; he could hear Gwaine and Alator's footsteps behind him but they weren't close enough to catch him before he reached the cave, which stank of fire and blood, so much blood, because Gaius was dead and Agravaine was dying, lying by the stone altar in the center of the room with a stab wound in his belly where Gwaine had gotten to him. Merlin hardly spared a glance for him as he went to Gaius, whose face was twisted in pain and whose neck gaped at him with a hideous dark smile. "_Gaius_," he choked, laying a trembling hand over Gaius' throat as if he could heal him through sheer willpower.

Alator and Gwaine emerged from the tunnels, breathing heavily, and Merlin rounded on the Catha. "It's not too late, is it?" he demanded, and Alator looked bewildered. "To heal him. It's not too late."

Alator's expression was sad and pitying as he looked at him, but Merlin didn't wait to hear his answer before turning back. He held his hands over Gaius, ignoring Gwaine's question of "Merlin — what?" and trying to remember every healing spell he had ever come across. "_Gestepe hole! Þurhhæle!_" he said fiercely. "_Þurhhæle bræd!_"

But nothing happened, not for any of the incantations, and there were many. He recited every healing spell he'd ever read about, even those he'd never tried before, until there was one more — only one more that he could think of, the one that the dragon had taught him to save Morgana so long ago, and if this didn't work then all was lost. Merlin closed his eyes and concentrated, focused every ounce of his power on it, and said, "_Ic þe þurhhæle þin licsare mid þam sundorcræftas þære ealdaþ æ!_"

And finally there was a change — the flesh of Gaius' throat knitted itself back together, until only the blood remained to show for the injury. Merlin waited with breathless hope for Gaius' eyes to open, for his chest to rise and fall, for the merest twitch of his fingers to show that he was alive, but seconds passed and there was nothing. "No," he breathed, crushed anew with his loss, because he'd been sure he could save him, so sure, and now all his magic seemed for naught.

A gentle hand on his shoulder made Merlin jump, and he turned to see Alator looking weak and horrified. "Emrys," he said softly. "Emrys, I'm sorry, but he is gone beyond even your power. Only those with the power of life and death could make a difference now."

Of course. _Of course_. He stepped away from Alator with a feverish grin, and recited one last incantation.

"_Ælífcælc, cume to mé._"

He could hear Alator's sharp intake of breath behind him, could feel Gwaine's eyes on him, but ignored it all as the air around him shifted and formed into a golden chalice that he hadn't seen in years. He caught the Cup of Life as it fell and felt its magic down to his bones, like a lightning bolt, like a tempest wind, and then he turned away from Gaius and went to Agravaine, and as he stood over him he drowned in hatred, hatred for all the months of lies and betrayal that led up to this final, unforgivable act. He wanted to say something to Agravaine as he writhed pathetically on the ground, gasping wetly and bleeding, suffocating and wheezing and dying in agony but not nearly quickly enough. He wanted to say something to him to impart the depths of his loathing, but he couldn't think of anything sufficient, so he simply knelt down, looked Agravaine in the eye, and made him watch as he stopped his heart without a word.

"Your flask, Gwaine," he said quietly, standing up with his mind full of Agravaine's death. Gwaine handed it over mutely, his eyes wide and his lips pressed tight, and Merlin knew that he should be sorry to be frightening his friend in this way and gutted that his friend would fear him at all, but still he felt nothing. Instead he poured the liquid into the cup — water this time, thank the gods, he wouldn't have to change it over — and returned to Gaius.

And as he tipped the water into Gaius' mouth, he offered up Agravaine's life for Gaius' with every ounce of his power and will, and with it a prayer: _Don't leave me. Don't leave me alone. Don't leave me alone_. If Gaius was dead then with him died Merlin's secret, because he was the only one who knew — and he was the only one who knew _everything_, all that Merlin had done and all that Merlin had suffered. But the seconds ticked by and Gaius still did not stir, and Merlin did not understand — the power of life and death had never failed him before, yet Agravaine was dead and so was Gaius, permanently, and the only explanation that he could think of was that the gods wanted him to be on his own, and that his destiny had claimed another victim.

No one spoke as Merlin's breathing became quicker, and he rocked back and forth and kneaded the hem of his shirt because he couldn't, couldn't break. "_Áfeorse_," Merlin burst out when it became too much to bear, flinging the Cup to the side, and it vanished into thin air, lost to the ether because he hadn't bothered to give it a direction. He stared down at his hands, covered in blood that was slowly turning brown in the cold air, and idly thought, _I knew that this would happen_.

"Emrys," Alator whispered before he could examine the full import of that thought, and knelt again. "Emrys, I — I cannot — forgive me, Emrys, for my part in this."

"Alator," Merlin began, but then stopped, because Alator _had_ played a role in this; he had kidnapped Gaius, tortured him, weakened him, and without him Gaius would have been safe and home and alive. _No_, Merlin told himself as anger began to wash over him. _No, this is Morgana's fault. This is all Morgana's fault._ "I forgive you," Merlin finally continued tiredly. "And I thank you for your allegiance. But please — please go. Please go."

Alator got to his feet and bowed once more. "It was an honor to meet you. A true honor," he said. "And — and I'm sorry." And then he was gone, and there was silence once more. Except—

"Merlin," Gwaine said behind him. "Merlin, I'm — I'm — _gods_." And it was then that Merlin remembered that Gwaine hadn't known about his magic, and turned around expecting condemnation; but Gwaine's eyes were crinkled with grief and he looked at Merlin without fear, and all he said was, "I should've been faster."

"No," said Merlin hoarsely. "No, don't — don't blame yourself. You — I didn't even ask you to come. I told Arthur—" And suddenly his earlier thought came crashing down with all the weight of its implications. He had told Arthur that this would happen, he had told Arthur that Agravaine would betray him, he had known that Gaius' life was in danger — but Arthur had refused to hear a word, and now Gaius was dead. "It's not your fault," he told Gwaine. "It's Morgana's."

But maybe, he realized, it was a little bit Arthur's fault too.

- -o- -

They rode back to Camelot, Merlin holding Gaius' body gently in front of him. Agravaine, wrapped in his cloak, was draped over his own black horse, who snorted and rolled its eyes at the stench of his blood but stood still and calm when Merlin whispered a few words in its ear. Their arrival at the gates caused a massive upheaval but they did not stop, and as they rode through the streets, Merlin could hear the people talking.

"Gaius? Is that Gaius?"

"Is he dead?"

"What's that black bundle, there?"

"Isn't that Lord Agravaine's horse?"

"Look at all that blood!"

"I told you he weren't a traitor!"

"_Gaius?_"

And Merlin was glad to pass through the gates into the courtyard because it meant fewer prying eyes, although now the guards were crowding around them and asking questions, and Merlin was forced to hand over Gaius' body to Sir Leon, who was pale and tight-lipped, and suddenly Merlin couldn't take it anymore. In all the clamor of the discovery of Agravaine's treachery as they unwrapped his body, Merlin slipped away from the crowd to find a place where he could be alone.

He found himself in Arthur's room out of habit because he didn't want to go back to his own, where he would wander amidst the familiar clutter and see Gaius everywhere — standing by the bench that was blackened by accidental fire, pitted and scarred by the remedies that Gaius had cooked up over the years; perched precariously on the ladder to his beloved books, the ladder he had fallen off of all those years ago when Merlin had first walked through his door; hunched over the dinner table, hiding a plate from Merlin with a twinkle in his eye and a mouthful of chicken, saying, "_You said you didn't deserve it_." He couldn't bear to go back there, where the memories would drown him, so he stared into the courtyard and hardly even heard Arthur when he came in.

"Merlin," Arthur said. "I just heard. I didn't expect you — I thought you'd be—" _with Gaius_, he didn't say, but Merlin heard it still, and didn't answer.

He could hear Arthur moving around behind him — dropping his sword on the table, stripping off his belt, moving a chair — and still he said nothing. Instead he watched the courtyard below as people from the lower town crowded in to get news; and as they began reacting in horror and tears, Merlin couldn't bear to look any longer, and instead examined the flagstones, finding all the spots that he had missed when he had last scrubbed the floor until Arthur spoke again.

"I didn't know about... about Agravaine." There was a pause where Arthur waited for Merlin to talk, because silence had never been a problem before, but when no response was forthcoming Arthur finally continued. "I just — he'd never shown signs of — how could I have known?"

There were a hundred reasons that Merlin could have listed off for him, and all of them started with '_Because I told you_.' But Arthur wouldn't listen, had never listened, and Merlin couldn't be bothered to try anymore.

"He was my uncle," Arthur said when Merlin still didn't respond, and it sounded like a plea for the understanding that Merlin had always given him in the past, always, no matter the circumstance or the atrocity — but not today, and never again.

"He was my _father_," Merlin answered roughly, and Arthur didn't seem to know what to say.

"Y—Yes. And that was why I couldn't take your word—"

And Merlin turned around with muted fury in his eyes, and Arthur fell silent. "_Couldn't take my word for it_," Merlin repeated, and even in his anger his heart broke again, because deep down he had been hoping that he would forgive Arthur even for this, that Arthur would talk him into staying without knowing that he was doing so, because Merlin had already decided that he needed to get out. But if this was how he truly felt — if, after all this time, he still didn't believe anything Merlin said — then it truly had been for nothing. "_I warned you_," he said furiously. "I warned you again and again, long before Gaius was kidnapped — and you refused to listen to me. You always do. And now — and now Gaius is dead because of it. Because you _wouldn't_ take my word for it."

He was trembling now, and Arthur moved forward in concern. "I'm sorry," he said, and put a hand on Merlin's shoulder. "I should have listened to you. I know that now, and I'm sorry." And Merlin could hear himself being patronized; he could hear the placation and the empty words, and he knew that he'd always be hearing it, because nothing would ever change. He had always longed for the day when Arthur would see him for who he truly was, but there needed to be trust there first, and if Arthur didn't trust him even after all he'd done—

"This isn't the first time," Merlin said, wrenching out Arthur's grasp. "For years — ever since _Valiant_ I've come to you when something was wrong, and every time you laugh at me, or tell me I'm an idiot, or _threaten me with exile_, and every time I'm proven right."

Arthur was frowning at him now, ready to protest, but Merlin was not ready to hear it. "Valiant. Anhorra. Sigan. Catrina. _Agravaine_. There are so many times — Arthur, why don't you listen to me? Why don't you _trust_ me? I have been by your side for so long — I have saved your life so many times, and I have never left you, _never_, and you still — you still don't _trust me_." Arthur was staring, and Merlin closed his eyes and took a deep breath to calm himself before adding quietly, "Have I ever led you astray?"

Arthur deflated. "No, I — I suppose you haven't," he conceded. "And I do trust you. I do. But you have to admit... you have to admit that the things you tell me sometimes — well, they sound ridiculous. And they're just hard to believe."

"And that," Merlin said, suddenly exhausted, "is the very definition of trust."

The silence between them was thick and heavy and suffocating, and there was a dawning comprehension on Arthur's face that something deeper, something much more serious than grief was at work here.

"But Merlin," said Arthur, and Merlin had never heard such uncertainty in his voice before. "I _do_ trust you. I trust you more than — than—"

"Agravaine?" Merlin finished for him, and even though Arthur flinched, he couldn't bring himself to feel cruel.

"Yes," Arthur plowed on, and Merlin wanted to laugh because it was just so _Arthur_ to continue after that, but he was far too numb to laugh. "Because you're right, you've been with me through everything - you've been my servant for years now, and my — my friend for just as long—" and Merlin couldn't help but notice how it still pained Arthur to admit that they were friends, even in private, and while yesterday he would have passed it off as normal, now he wondered if there was a deeper reason why it was so difficult. "And I swear that I'll listen to you next time — I promise that nothing like this will ever happen again-"

"I'm leaving, Arthur," Merlin said abruptly, because there wouldn't be a next time, and the words fell between them, irretrievable and true, and suddenly all Merlin wanted was to be gone.

Arthur stared at him, mouth agape, and for a moment Merlin thought he saw a glimpse of real horror in his eyes — but then Arthur shook his head and said, "No. Merlin, I know you're upset—"

"Upset," Merlin said dispassionately, and shook his head. "No, I'm not upset. I'm — I don't know what I am, anymore—"

"You can't go, Merlin. I can't — I can't lose Gaius and you both," said Arthur desperately, moved to honesty, but Merlin had had enough.

"You have lost a friend, Arthur Pendragon," Merlin said, turning back and throwing Arthur's words at him. "You have lost—" But Arthur didn't know what he had lost, and never would — he would never know that he had lost the one true friendship that he had, that he had lost his protector and his destiny, and Merlin said nothing of it as he let the door fall shut between them, leaving Arthur standing bereft.

- -o- -

He went to Gwen's house next to say goodbye. She opened the door, clutching the bottle of perfume that Gaius had made her for her last birthday, with red eyes and tears streaming down her face. "Oh, _Merlin_," she sobbed, and flung her arms around him, burying her head in his shoulder.

And he cried then too, just a little, because he was never going to see Gwen again and he would miss her desperately. And she held him then like his mother used to, comforting and safe and surrounding him with love, and he wept again because Gwen would make a wonderful mother but would never be one, because she loved Arthur and he was going to die. He was going to die because he would never survive without Merlin, and Merlin knew this but could no longer bring himself to care. He cared about Gwen, and hated himself for the role he would play in her sadness, but it wasn't enough; Gwen's future grief was not enough to keep him here, not in the face of all the past and present sacrifices that Merlin had made only to be met time and time again with distrust and disbelief.

"I miss him too," Gwen said, and Merlin choked on a sob because he hadn't wept for Gaius and never would because the grief he felt for Gaius was a dark space that he dared not explore. Losing Gaius had opened a chasm beneath all the reasons he had for staying, a chasm that had found all the cracks in his willpower and shaken them until it all crumbled to dust.

He briefly considered just not telling her that he was leaving — it would be easier, because she would not understand his reasons; and it would be harder to go if she pleaded with him to stay. But she deserved better than that — he had seen her previous devastation when others left her without saying goodbye - so Merlin finally broke the news, but when she assumed that he meant that he was going home to visit his mother he did not correct her. And then he wanted to be alone again — he wanted to leave Camelot, leave it all behind, but Gwen insisted that he stay for dinner, and he could not begrudge her these last hours because he knew that he would regret it if he didn't spend them with her.

When he finally did leave, she hugged him hard and long and said, "Come back quick." And still he did not tell her that he would never be back; he only squeezed her tight and said, "Goodbye, Gwen. I'll miss you." And as she closed the door behind him he whispered, "And I'm sorry."

- -o- -

When he left Camelot the next morning there was only one place that he could think of to go — especially after spending the night in Gaius' chambers, which already seemed empty and lifeless without him. Waking up alone without Gaius prodding him out of bed made his death seem all the more real, and when he was finally on the road all the mess of emotions he had kept bottled inside turned to rage, and it festered and festered until it physically burnt him. By then he was hurtling through the woods, taking a path he had only been on once before until he stood before the little hut in the valley, trembling with anger.

She opened the door warily, and backed up in astonishment when she saw that it was him. "_Merlin_," she spat, and Merlin had never hated her more. "What are you doing here? Come to let me finish the job?"

_You killed Gaius_, he wanted to shout, but he coiled his rage within him and said instead, "I know who Emrys is."

The change was instantaneous; even though it was laced with distrust and disbelief, Morgana surged forward eagerly. "Who?" she demanded. "_Tell me!_"

He leaned forward then, close enough to kiss, and as he looked into her crazed eyes he remembered the girl she used to be, and with that memory came the memory of what he once would have done to keep Arthur safe. But that stage of his life was over, except perhaps for this, the first selfish act he had ever done in his life: revenge. And he leaned closer still, until his lips were next to her ear, and whispered, "Me."

And he allowed her just enough time for his confession to sink in before he killed her, leaving her wide-eyed and betrayed, his last gift to the destiny that could no longer be.


End file.
